In the art of product handling apparatus, there is a group of product stacking devices known as down stackers. These downstacker devices receive product (usually cartons or packages) from an infeed conveyor that is operable to provide a space or gap between adjacent cartons. The space between adjacent products is usually a gap approximating the products length. The product is delivered to a stacking chamber by the conveyor and the product is dropped onto lowerating device which moves downwardly as the product comes in. Once the stacking chamber has the proper number of vertically stacked product in it, the incoming products are then clamped to a stop while a pusher mechanism pushes the accumulated product out of the stacking The pusher then retracts and the lowerating mechanism cycle starts over again. This continues until the proper number of stacks are accumulated in the stack accumulation area at which time the stacked product may be loaded into a case mechanically or hand packed off as desired. These prior art downstacker devices involve an interrupted operation and are not continuous.